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mdj or revised floodway reflecting the lJost-project condition. (c) Upon completion of the proposed :!ncroachments. a community shall ~rovide as-built certifications in ac- ,ordance with the provisions of i 65.3 )f this part. The Administrator will, initiate a finai map revision upon reo ,eipt of such certiflcations in accord- mce with Part 67 of this subchapter. :53 FR 16279, May 6. 19881 j 65.13 Mapping and map revisions for areas subject to alluvial tan floodiJlg. This section describes the proce- jures to be followed and the types of nformation FEMA needs to recognize )n a NFIP map that a structural flood :ontrol measure provides protection :rom the base flood in an area subject ;0 alluviai fan flooding. This informa- ;ion must be supplled to FEMA by the mmmunity or other party seeking ree- )gnition of such a flood control meas- Jre at the time a flood risk stud~ or ,estudy is conducted, when a map revi. lion under the provisions of part 65 of ;his subchapter is sought, and upon 'equest by the Administrator during ;he review of previously recognized 100d controi measures. The FEMA 'eview will be for the sole purpose of ,stablishing appropriate risk zone de- ;erminatlons for NFIP maps and snail lOt constitute a determination by "EMA as to how the flood control neasure will perform in a flood event. I (a) The applicable provisions of ! 65.2, 65.3, 65.4, 65.6, 65.8 and 66.10 hall also apply to FIRM revisions in- olving alluvial fan flooding. (b) The provisions of i 65.5 regard. g map revisions based on fill and the rovislons of part 70 of this chapter hall not apply to FIRM revisions in- olving alluvial fan flooding. In gener, I, elevations of a parcel of land or a tructure by fill or other means, will at serve as a basis for removing areas hject to alluvial fan, flooding from area of special food hazards.. (c) FEMA will credit on NFIP maps nly major structural flood control easures whose design and construc- on are supported by sound engineer- g analyses which demonstrate tl1at e measures will effectively elimln"te luvial fan flood hazards from the ea protected by such measures. The provided analyses must include, but are not necessarily limited to, the fol. lowing: (1) Engineering analyses that quan- tify the discharges and volumes of water, debris, and sediment movement associated with the flood that has a one-percent probability of being ex- ceeded in any year at the "pex under current watershed conditions and under potential a.dverse conditions (e.g., deforestation of the watershed by fire). The potential for debris flow and sediment movement must be as- sessed using an engineering method acceptable to FEMA. The assessment should consider the characteristics and availability of sediment in tl1e drainage basin above the apex and on the alluvial fan. (2) Engineering analyses showing that the measures will acconunodate the estimated peak discharges and vol- umes of water, debris, and sediment, as determined in accord""ce with paragraph (c)(l) of this section, and will withstand the associated hydrody- namic and hy<1rostatic forces. (3) Engineering analyses showing that the measures have been designed to withstand the potential erosion and scour associated with estimated dis- charges. (4) Engineering analyses or evidence Showing that the measures will pro- vide protection from hazardS associat- ed with the possible relocation of flow paths from other parts of the fan. (5) Engineering analys~s that assess the effect of the project on flood haz- ards, including depth and velocity of floodwaters and scour and sediment deposition, on other areas of the fan. (6) Engineering analyses demon. strating that flooding from scources other than the fan apex, including local runoff, is either insignificant or has been accounted for in tIle design. (d) Coordination. FEMA will recog- nize measures that are adequately de- signed and constructed, provided that: evidence Is submitted to show that the impact of the measures on flood haz- ards in all areas of the fan (inCluding those not protected by the flood con- trol measures), and the design and maintenance requirements of the measures, were reviewed ,and approved by the impacted communities, and also 362